Removal

Cylinder Head Assembly

Front Plate Removal Disassembly Steps
1. Crankshaft pulley bolt
2. Timing belt cover
3. Timing belt
4. Tension pulley and tension spring
5. Crankshaft timing pulley
6 Camshaft timing pulley
7. Camshaft boss
8. Oil pump and pulley
9 Water pump
10. Frontplate

Important Operations Service and Repair
1. Timing belt
2. Tension pulley and tension spring
(a) Remove the tension spring.
(b) Loosen bolt (B) draw the tension pulley fully to the water pump side.
(c) Remove the timing belt.
(d) Remove the tension pulley.
(e) Remove the crank timing pulley and guide plate.

3. Camshaft timing pulley
Apply a detention to the pulley by putting a T-bar wrench or other proper tool over the front-plate fitting bolt, and loosen the pulley fitting bolt.

4. Oil pump with pulley
Use a 6 mm Allen wrench to remove the oil pump along with the oil pump timing pulley and the rotor.

Rocker Arm Shafts Disassembly Steps
1. Nut; rocker arm spring
2. Bolt; rocker arm bracket
3. Rocker arm spring
4. Rocker arm shaft
5. Rocker arm
6. Bracket

(a) Rocker arm shaft assembly
Sequentially loosen and remove the rocker arm shaft tightening nuts from the outermost one, and remove the rocker arm shaft with the brackets an assembly.

Cylinder Head Disassembly steps
1. Rocker arm shaft assembly
2. Camshaft
3. Cylinder head assembly
4. Cylinder head gasket

(a) Cylinder Head Assembly
Loosen the head bolts evenly from the outermost one using an extension bar wrench and thereby remove the cylinder head. Remove the gasket at this time. Extension bar wrench : J-24339-O1

Valve Springs Disassembly Steps
1. Split collars
2. Upper spring seat
3. Valve spring
4. Oil controller
5. Valve
6. Lower spring seat

Inspection and Repair
Make necessary corrections or parts replacement, if ware, damage or any other abnormal conditions are found during inspection.

Note: Wash and clean each part detached. Remove all dirt, carbon, contaminated oil, rust, lint and other foreign matter. Care must be taken to avoid damage when removing carbon from piston, cylinder heads, valves and other parts. Use compressed air to remove foreign matter in the oil hole of each part, and insure there is no blockage or restriction what so ever.

Cylinder Head Visual Check
Remove carbon adhering to the lower face while taking care not to damage the valve seat and other parts, and check for cracks and damage.

Distortion of lower face:
Make six measurements on the four sides and the diagonals, and if the limit is exceeded make necessary correction or replacement

Distortion of manifold face:
Make measurement in a manner similar to that for the cylinder head. If the limit is exceeded make necessary corrections.

Combustion chamber
Remove adhering carbon and inspect the combustion chamber inside, spark plug hole, valve seat insert engagement section and other parts. If there is a crack or considerable damage replace it with a new one.

Cylinder Body Distortion of upper face:
Make measurements on the four sides and the diagonals with a straightedge and thickness gauge as shown in the figure. If the limit is exceeded make necessary correction or replacement

VALVE

Valve stem diameter.

When the wear is beyond the limit for use or when a considerable wear or seizure is found, replace it with a new one.

Head edge thickness:
If the limit is exceeded, replace it and the valve guide as a pair.

Valve Springs

If the limit is exceeded, replace it with a new one.

Inclination

Tension (when compressed to the specified height)

Valve Guide

Clearance between valve stem and valve guide:

Set a dial gauge as shown in the figure and measure the clearance between the valve guide and valve stem.

Valve guide replacement
Hit the valve guide out from the combustion chamber side to the cam side using a valve guide remover. Valve guide remover J-26512-1

Apply engine oil to the outer circumference of the valve guide and hit it in, with a valve guide installer, until the top end of the installer hits the cylinder head.
Height of valve guide upper-end from cylinder: 16.1 - 16.3 mm (0.634 - 0.642 in.) Valve guide installer: J-26512 (J-26512-1) (J-26512-2)
Valve Seat
Valve seat insert

1. Attach a new valve to the cylinder head and measure the amount of sinking from the head surface with a depth gauge. If the limit is exceeded, replace the valve seat insert

2. If the seat contact surface is damaged or made rough or if the wear of the contact width exceeds the limit, make necessary correction.
Correction of valve seat

1. Remove carbon from the seat surface, cut to the minimum extent to remove flaws and roughness of the seat surface with 30°, 90°and 150° valve seat cutters, and thus correct the contact width to a standard value.

2. Apply compound to the valve seat surface and fit while turning the valve and hitting light Insure that the whole circumference contacts the valve in the center of the valve seat surface and that the valve seat contact width is a standard value.
Valve seat insert replacement

1. Arc-weld, at several points, a rod to draw it out into the valve seat, while taking care to avoid damage to the aluminum section.
2. When the cylinder head heated by welding is cooled by air for 2 to 5 minutes, the valve seat shrinks because of local cooling of the valve seat So give a shock to the welded rod and draw it out

3. Clean the valve seat press-fit section on the cylinder head side while taking care to avoid damage to it, heat and expand the insert press-fit section using steam or other means, and press fit horizontally the valve seat cooled and contracted with dry ice or other means.

ROCKER ARM SHAFT AND ARM ASSEMBLY
Visually inspect for damage or other abnormal conditions.

Run-out:
Standard: 0.2 (0.008) or less mm (in.)
Limit: 0.4 (0.016) mm (in.)

Diameter:

Make measurement on four rocker arm fitting positions, and if the limit is exceeded, replace it with a new one

Clearance between rocker arm shaft and rocker arm:
Measure the inner diameter of the rocker arm, and if the clearance between it and the outer diameter of the rocker arm shaft exceeds the limit, replace the rocker arm or shaft.
Standard: 0.005 - 0.0045 (0.002 - 0.0018) mm (in.)
Limit: 0.2 (0.0078) mm (in.)
Camshaft Assembly
Visual check